The present invention relates to improvements to materials and processes used in oenology. It is known that during the vinification of a must, temperature conditions are one of the most important factors in producing of a quality wine. For several years, indeed, studies by researchers have shown that the physical qualities are at least as important, if not more so, than the chemical conditions of the fermentation and vinification.
A minimal temperature must be reached in order for the alcoholic fermentation to begin. However, after a certain time, the release of heat is such that the temperature can rise sharply with destruction of the yeasts, the premature cessation of the sugar-alcohol transformation and deterioration of the quality of the wine.
On the other hand, if the temperature is too low, the fermentation of the must starts slowly and under poor conditions.
Empirical solutions for cooling or heating (trickling on the vats, water circulation exchanger, vat fractionning . . . ) are used in the wine storehouses to overcome these problems, without being certain of attaining the optimal quality desired.
The integral control of the wine throughout the fermentation period must provide, through physical processes, a product requiring progressively fewer corrections by chemical treatments.
According to the present application, the invention concerns the improvement of traditional techniques and the adaptation of existing installations or installations having several vats.
Since the invention corresponds to a type of installation that is particularly flexible and adaptable to the most diverse cases, it is necessary, in order to avoid considerable investment, to provide very flexible arrangements and to ensure that they perform well. Several preliminary remarks are, in fact, necessary.
It is evident that when taking into consideration installations such as those of FIG. 1, which will be described herein-below, numerous apparatus can be common to several vats. Furthermore, it has been noted that in most of the existing vats, due to the aerobic character of the fermentation phenomena, the most of the reaction occurs adjacent to the surface of the liquid mass; it is noted in particular temperature gradients of about 10.degree. C. in the liquid layer of about two meters under the surface and the "cap" forms whereas below this upper layer, the homogeneity of temperature is very noticeable, the gradients being very slight. It can thus be said that at most it would be useless to intervene beneath a depth of approximately two meters, but this allows devices to be envisaged according to the present invention, a large part of which is disposed towards the top of the vat.
It is noted in a surprising manner that the introduction through the top part of all the elements intervening in the vat not only considerably simplifies the adaptation to all existing vats, but considerably improves its yield when it is essentially the reactional mass the closest to the air that is treated according to the invention.
Furthermore, it has been noted that due to the present invention and this is most surprising, by adjusting the regulating program it is possible, from the same vintage to obtain wines that are extremely different, althrough they originate from the same grapes.
In order to do this according to an essential characteristic of the invention, it is introduced through the upper opening of the vat a plunging column containing all or part of the intervention and collection devices according to the invention (drawing off and injecting fluids, temperature control, etc . . . ). In other words, all the elements contained in the vat K of FIG. 1 can be gathered in this plunging column.
Furthermore, the plunging column of a series of vats are adapted in such a way that they can be placed in relation with central control and regulating equipment, and a central thermal energy or refrigeration supply.
Thus, it is possible from the same raw material to obtain according to the vats and programs, identical or very different wines, as will be shown by the following examples.
Another characteristic of the invention is bound to the fact that the analysis of the thermal evolution of a vat during vinification, shows the presence of a temperature gradient or, further, the existence of at least two distinct temperature zones, which, due to the particularities of the injection system described herein-under, only execute the programmed adjustment of a part of the vat and consequently to reduce the quantity of energy required (heating and refrigeration). This reduction can reach or exceed 50% of the total energy normally required.
In order that the technical characteristics and advantages of the present invention be better understood, examples of embodiments will be described which, of course, in no way limit the scope and application of said invention.